P0520 DTC Code: Detailed Analysis and Solutions


In the world of automotive diagnostics, DTC codes play a vital role in identifying and troubleshooting various issues in vehicles. In this comprehensive article, we will dive deep into the P0520 DTC code and explore its significance, causes, symptoms, and potential solutions. So, let’s get started!

Understanding the P0520 DTC Code

The P0520 Diagnostic Trouble Code (DTC) is related to the engine oil pressure sensor/switch circuit malfunction. It typically occurs in vehicles with electronic oil pressure sensors or switches. When the ECM (Engine Control Module) detects a deviation from the specified voltage range, the P0520 code is triggered and recorded.

Causes of the P0520 DTC Code

There are several potential causes behind the occurrence of the P0520 DTC code. These include:

  1. Faulty Engine Oil Pressure Sensor/Switch: A damaged or malfunctioning oil pressure sensor or switch can result in an abnormal voltage reading, triggering the P0520 DTC code.

  2. Wiring Issues: Damaged or loose wiring connections between the ECM and the oil pressure sensor/switch may cause an irregular voltage signal, leading to the code’s activation.

  3. Low Engine Oil Level: Inadequate engine oil level can affect the oil pressure and cause abnormal readings, which, in turn, can result in the triggering of the P0520 code.

  4. Engine Oil Pump Problems: Malfunctioning or clogged oil pumps can lead to inadequate oil pressure; this, in turn, can affect the readings and activate the P0520 code.

Symptoms of the P0520 DTC Code

When a vehicle displays the P0520 trouble code, it may exhibit various symptoms, including:

  • Malfunctioning Oil Pressure Gauge: The oil pressure gauge on the dashboard may not read accurately, showing lower or higher than normal pressure levels.

  • Warning Lights: The check engine light (CEL) may illuminate, indicating a potential issue in the engine oil pressure system.

  • Reduced Engine Performance: The engine may experience a noticeable decrease in performance, such as rough idling or hesitation during acceleration.

  • Engine Shutdown: In extreme cases, the ECM may trigger a fail-safe mode, shutting down the engine to prevent further damage due to low oil pressure.

Diagnostic Process for the P0520 DTC Code

When faced with the P0520 DTC code, a thorough diagnostic process is essential to pinpoint the exact cause of the issue. Here’s a step-by-step guide to diagnosing and resolving the P0520 code:

Step 1: Use an OBD-II Scanner

Connect an OBD-II scanner to the vehicle’s OBD-II port to retrieve the trouble codes stored in the ECM. This will confirm the presence of the P0520 code and help identify any additional codes related to the issue.

Step 2: Inspect the Wiring and Connectors

Carefully examine the wiring harness and connectors associated with the oil pressure sensor/switch. Look for any signs of damage, such as frayed wires or loose connections. Repair or replace any faulty components as necessary.

Step 3: Check Engine Oil Level and Condition

Ensure that the engine oil is at the correct level and in good condition. Low oil levels or dirty oil can affect the oil pressure readings. If needed, top up the oil or perform an oil change using the manufacturer-recommended oil type and viscosity.

Step 4: Test the Engine Oil Pressure Sensor/Switch

Use a multimeter to test the electrical resistance of the oil pressure sensor/switch. Compare the readings to the manufacturer’s specifications. Replace the sensor/switch if it falls outside the acceptable range.

Step 5: Inspect the Oil Pump

Visually inspect the oil pump for any signs of damage or clogs. Remove the oil pan if necessary to access the pump. Clean or replace the pump if it is malfunctioning or blocked.

Step 6: Clear the Trouble Codes and Test Drive

Once the necessary repairs have been made, clear the trouble codes using the OBD-II scanner. Take the vehicle for a test drive to verify that the P0520 code does not reappear and that the oil pressure readings are within the normal range.

Frequently Asked Questions

Q1: Can I continue driving with the P0520 DTC code?

A1: It is not recommended to drive your vehicle with the P0520 code present, as it signifies a potential issue with the engine oil pressure system. Continuing to operate the vehicle may cause severe engine damage. Seek professional assistance to diagnose and resolve the problem promptly.

Q2: How much does it cost to repair the P0520 DTC code?

A2: The cost of repairing the P0520 DTC code can vary depending on the exact cause of the issue, the vehicle’s make and model, and labor rates in your area. It is advisable to consult with a qualified mechanic or service center to obtain an accurate estimate.

Q3: How often should I check my engine oil level?

A3: It is recommended to check your engine oil level at least once a month or before embarking on long journeys. Ensuring adequate engine oil is crucial for optimal engine performance and preventing potential issues like the P0520 code.


The P0520 DTC code can be an indicator of underlying problems in your vehicle’s engine oil pressure system. By understanding its causes, symptoms, and diagnostic process, you can effectively address the issue before any serious damage occurs. Remember, consulting a professional mechanic or automotive technician is always advised for accurate diagnosis and proper resolution.

About author


Meet Sam Mitchell, your experienced and reliable guide in the complex world of car fault codes. With a robust career spanning over 15 years as a professional car mechanic, John has the skills, knowledge, and practical experience to help you navigate car fault issues with confidence.


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